SN1 Reactions in Supercritical Carbon Dioxide in the Presence of Alcohols: the Role of Preferential Solvation

Autor: Rossella Mello, María Elena González-Núñez, Rafael Acerete, Thais Delgado-Abad, Gregorio Asensio, Jaime Martínez-Ferrer
Jazyk: angličtina
Rok vydání: 2016
Předmět:
Zdroj: Delgado Abad, Thais Martínez Ferrer, Jaime Acerete, Rafael Asensio Aguilar, Gregorio Mello, Rossella C. C. González Núñez, María Elena 2016 SN1 Reactions in Supercritical Carbon Dioxide in the Presence of Alcohols: the Role of Preferential Solvation Organic & Biomolecular Chemistry 14 6554 6560
RODERIC. Repositorio Institucional de la Universitat de Valéncia
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Popis: Ethanol (3b) inhibits SN1 reactions of alkyl halides 1 in supercritical carbon dioxide (scCO2) and gives no ethers as products. The unexpected behaviour of alcohols 3 in the reaction of alkyl halides 1 with 1,3-dimethoxybenzene (2) in scCO2 under different conditions is rationalised in terms of Bronsted and Lewis acid–base equilibria of reagents, intermediates, additives and products in a singular solvent characterised by: (i) the strong quadrupole and Lewis acid character of carbon dioxide, which hinders SN2 paths by strongly solvating basic solutes; (ii) the weak Lewis base character of carbon dioxide, which prevents it from behaving as a proton sink; (iii) the compressible nature of scCO2, which enhances the impact of preferential solvation on carbon dioxide availability for the solvent-demanding rate determining step.
Databáze: OpenAIRE